/**
 * Token generator — reads bytelyst.tokens.json, outputs 4 platform formats:
 *   1. CSS custom properties (tokens.css)
 *   2. TypeScript constants (tokens.ts)
 *   3. Kotlin object (MindLystTokens.kt) — for KMP shared module
 *   4. Swift structs (MindLystTheme.swift) — for iOS SwiftUI
 *
 * Usage: tsx scripts/generate.ts
 */

import { readFileSync, writeFileSync, mkdirSync } from "node:fs";
import { resolve, dirname } from "node:path";
import { fileURLToPath } from "node:url";

const __dirname = dirname(fileURLToPath(import.meta.url));
const tokensPath = resolve(__dirname, "../tokens/bytelyst.tokens.json");
const outDir = resolve(__dirname, "../generated");

mkdirSync(outDir, { recursive: true });

const tokens = JSON.parse(readFileSync(tokensPath, "utf-8"));

// ── 1. CSS ───────────────────────────────────────────────────────────
function generateCSS(): string {
  const lines: string[] = [
    "/* Auto-generated from bytelyst.tokens.json — do not edit manually */",
    "",
    ":root {",
  ];

  // Semantic colors (dark theme as default)
  for (const [key, value] of Object.entries(tokens.color.semantic.dark)) {
    lines.push(`  --ml-${camelToKebab(key)}: ${value};`);
  }

  // Typography
  for (const [key, value] of Object.entries(tokens.typography.fontFamily)) {
    lines.push(`  --ml-font-${key}: ${value};`);
  }
  for (const [key, value] of Object.entries(tokens.typography.fontSize)) {
    lines.push(`  --ml-text-${key}: ${value}px;`);
  }

  // Spacing
  for (const [key, value] of Object.entries(tokens.spacing)) {
    lines.push(`  --ml-space-${key}: ${value}px;`);
  }

  // Radius
  for (const [key, value] of Object.entries(tokens.radius)) {
    lines.push(`  --ml-radius-${key}: ${value}px;`);
  }

  // Elevation
  for (const [key, value] of Object.entries(tokens.elevation)) {
    lines.push(`  --ml-shadow-${key}: ${value};`);
  }

  lines.push("}", "");
  return lines.join("\n");
}

// ── 2. TypeScript ────────────────────────────────────────────────────
function generateTS(): string {
  return [
    "// Auto-generated from bytelyst.tokens.json — do not edit manually",
    "",
    `export const tokens = ${JSON.stringify(tokens, null, 2)} as const;`,
    "",
    "export type Tokens = typeof tokens;",
    "",
  ].join("\n");
}

// ── 3. Kotlin ────────────────────────────────────────────────────────
function generateKotlin(): string {
  const lines: string[] = [
    "// Auto-generated from bytelyst.tokens.json — do not edit manually",
    "package com.mindlyst.shared.theme",
    "",
    "object MindLystTokens {",
    "",
    "    // Semantic colors (dark)",
    "    object Colors {",
  ];

  for (const [key, value] of Object.entries(tokens.color.semantic.dark)) {
    if (typeof value === "string" && value.startsWith("#")) {
      const hex = value.replace("#", "");
      lines.push(`        const val ${key} = 0xFF${hex.toUpperCase()}`);
    }
  }

  lines.push("    }", "", "    // Brain gradients", "    object Brains {");
  for (const [name, grad] of Object.entries(tokens.color.brain) as [string, { from: string; to: string }][]) {
    const fromHex = grad.from.replace("#", "");
    const toHex = grad.to.replace("#", "");
    lines.push(`        val ${name}From = 0xFF${fromHex.toUpperCase()}`);
    lines.push(`        val ${name}To = 0xFF${toHex.toUpperCase()}`);
  }

  lines.push("    }", "", "    // Spacing (8pt grid)", "    object Spacing {");
  for (const [key, value] of Object.entries(tokens.spacing)) {
    lines.push(`        const val x${key} = ${value}`);
  }

  lines.push("    }", "", "    // Radius", "    object Radius {");
  for (const [key, value] of Object.entries(tokens.radius)) {
    lines.push(`        const val ${key} = ${value}`);
  }

  lines.push("    }", "}");
  return lines.join("\n");
}

// ── 4. Swift ─────────────────────────────────────────────────────────
function generateSwift(): string {
  const lines: string[] = [
    "// Auto-generated from bytelyst.tokens.json — do not edit manually",
    "import SwiftUI",
    "",
    "struct MindLystColors {",
  ];

  for (const [key, value] of Object.entries(tokens.color.semantic.dark)) {
    if (typeof value === "string" && value.startsWith("#")) {
      lines.push(`    static let ${key} = Color(hex: "${value}")`);
    }
  }

  lines.push("}", "", "struct MindLystSpacing {");
  for (const [key, value] of Object.entries(tokens.spacing)) {
    lines.push(`    static let x${key}: CGFloat = ${value}`);
  }

  lines.push("}", "", "struct MindLystRadius {");
  for (const [key, value] of Object.entries(tokens.radius)) {
    lines.push(`    static let ${key}: CGFloat = ${value}`);
  }

  lines.push("}");
  return lines.join("\n");
}

// ── Helpers ──────────────────────────────────────────────────────────
function camelToKebab(str: string): string {
  return str.replace(/([a-z])([A-Z])/g, "$1-$2").toLowerCase();
}

// ── Write all ────────────────────────────────────────────────────────
writeFileSync(resolve(outDir, "tokens.css"), generateCSS());
writeFileSync(resolve(outDir, "tokens.ts"), generateTS());
writeFileSync(resolve(outDir, "MindLystTokens.kt"), generateKotlin());
writeFileSync(resolve(outDir, "MindLystTheme.swift"), generateSwift());

console.log("Generated 4 token files in generated/");